Surface treatment functionalization of sodium hydroxide onto 3D printed porous Ti6Al4V for improved biological activities and osteogenic potencies

Abstract In the design of multifunctional orthopedic biomaterials, enhanced biological activities, reinforced mechanical property, improved hydrophilicity and osteo-compatibility are the essential criteria. For achieving these goals, here a bioactive multifunctional Ti6Al4V implant with nanowire structured surface topography is designed and fabricated using 3D printing technique. Selective laser melting (SLM) is applied to fabricate scaffold materials with diamond cellular structures to meet the requirements of load-bearing function of bone tissue. With the alkali treatment of sodium hydroxide, osteogenic layer of Na2Ti6O13 is generated on the porous Ti6Al4V, on which apatite is easily deposited and immobilized. Clusters of Na2Ti6O13 exhibits excellent hydrophilicity and surface roughness with precise control of alkali treatment time. Additionally, the compressive strength of the modified porous Ti6Al4V (121.2 MPa-84.5 MPa) decreases due to the corrosion of sodium hydroxide, while it can satisfy the basic mechanical requirement of cortical bone. The results prove that the surface-modified 3D printed porous Ti6Al4V possesses balanced mechanical strength and osteogenic function, promising for potential application in complex multifunctional bone defects.